How Is Asse to be decommissioned?

The Federal Office for Radiation Protection (BfS) has now presented the evaluation criteria for finding the best option for decommissioning the Asse mine. Since nobody exactly knows how long the Asse II mine will still be accessible for a methodical closure, BfS must decide as quickly as possible how the radioactive waste repository can be decommissioned as safely as possible. It is the objective of BfS to select the best of three decommissioning options currently under discussion.

It must be decided whether the waste will be retrieved, relocated into deeper parts of the mine, or whether Asse will be backfilled with a special type of concrete. To be able to take this pathbreaking decision in a transparent way, BfS in advance presented the evaluation criteria and the procedure for the selection of the best possible decommissioning option. The criteria were developed in coordination with the Asse II Accompanying Group (among others representation of the citizens’ initiatives). With these evaluation criteria, everyone should be in a position to comprehend why BfS proposes a certain decommissioning option which will be announced at the end of the year. This is a new procedure which will set standards for other procedures with respect to repositories.

In all considerations, the protection of the population and the mine staff during the decommissioning phase and in the post-closure phase has top priority for BfS. In the selection procedure, the three decommissioning options will be evaluated through 18 criteria. Each option will for example be examined for its radiological impact, whether it can be implemented technically and with respect to licensing, or what consequences would result from people unintentionally entering the mine. The criteria must match the following issues:

1. Safety in the operational phase
2. Impacts on the environment in case of an uncontrollable inflow of brine
3. Preliminary long-term safety assessments
4. Feasibility
5. Time required

The three decommissioning options will be evaluated in correspondence with these issues. This procedure ensures that the decision-making process will be comprehensible. Also the Comparison of Options Working Group (AGO) considers this procedure good.

By mid December, BfS will announce which decommissioning option is the safest one. Until then, the schedule is as follows:

1. It is estimated that the results of the feasibility and impact studies will be available at the beginning of October.
2. The studies will be published in the internet. The authors present their study results on the occasion of a public workshop.
3. Professional evaluation of the feasibility studies by BfS (approximately by mid December).
4. BfS presents the result in December.
5. The public have the opportunity to discuss the proposal. Questions, suggestions, and objections can be entered into the procedure.
6. BfS will pronounce the final decision about the decommissioning of Asse.

Kriterien zur Bewertung von Stilllegungsoptionen für das Endlager für radioaktive Abfälle Asse

Additional Comment of 9 September 2009 on the Press Release on the Criteria Report:

BfS presented the report on the evaluation criteria for the comparison of options for the selection of the best possible decommissioning option for the Asse II mine on 3 September 2009. The Federal Office gives the following comment on the report and the accompanying press release:

In May 2009, BfS published a first discussion paper which puts up for discussion various criteria and a proposal for an evaluation procedure. The Asse II Accompanying Group, the Comparison of Options working group, and the Federal Ministry for the Environment, Nature Conservation and Nuclear Safety made suggestions and statements on the discussion paper. The major part of these suggestions and recommendations was considered or taken over when the discussion paper was revised.

The participation of the accompanying bodies Comparison of Options working group and Asse II Accompanying Group occurred in the form of consultations where the parties involved could make suggestions and give recommendations. In a separate chapter of the criteria report, it is described how BfS has taken into account the suggestions and recommendations of the discussion paper’s revision and which contributions have been taken over (cf. pages 9 to 20 of the report and Annex 2). Thus, there has been reconcilement in terms of a request for and discussion of suggestions, but no reconcilement in the sense of a mutual agreement regarding contents. There may be another misunderstanding about the statement that AGO considers the procedure selected by BfS to be good. This statement only refers to the procedure of how the comparison of options proposed by BfS is to be carried out.

One issue has to be pointed out in particular: BfS has not acted on the suggestion of the Accompanying Group to include the so-called revisability in the catalogue of evaluation criteria. The criterion "revisability", which the Asse II Accompanying Group classified as important, was to help evaluate to what extent the planned decommissioning option can be “revoked” later on. Accordingly, a revision of the decommissioning option carried out could, for example, become necessary if the state of the art of science and technology advanced and one recognised that the previously planned decommissioning options had not been appropriate.

From the BfS point of view, the criterion “revisability” cannot be applied to all options in the same way since the options “relocation” and “complete backfilling” do not include the option of retrieving the waste and the option “retrieval” includes the revisability of a decision taken previously. As a result of this, “revisability” is not appropriate for a comparative evaluation and, thus, for a weighting process.

Irrespective of the determined criteria, it is planned to pick up the aspect of revisability within the scope of the comparison of options and to discuss it.